Chemical demulsification is a convenient and effective method in breaking water in oil and oil in water emulsions. Demulsification can be important for waste water handling and volume reduction, food production and processing, and even in chemical manufacturing.
Demulsification may be particularly important in the production of oil and gas for several reasons. One reason is because in the normal course of producing the oil and gas from a subterranean formation, at some point significant amounts of water may be co-produced with the oil and gas. When the water is co-produced as an emulsion, it is usually necessary to break the emulsion prior to transporting the oil to market.
The emulsion may be a natural emulsion due to the presence of naturally occurring emulsifying agents, or the emulsion may be an artifact of the use of additives or other recovery processes. For example, the use of steam and caustic injection or combustion processes, for in-situ recovery of heavy oils, may be complicated by the production of viscous emulsions of oil, water and clay. Crude oil may be found in a geological reservoir in association with gas and saline or fresh formation water. A natural emulsion may form simply due to shear and pressure drops at the well head, chokes and valves.